Fragile, Handle with Care

Radiating cables, also called leaky feeder cables, deliver reliable, high-frequency coverage for tunnels, hospitals, and even in shopping centres. They feature small slits or openings in the outer conductor along the entire length of the cable which allow a wireless signal to pass in and out. "With these cables, network providers are able to offer scalable and wireless broadband services, which are even required in larger building complexes as a preventative fire protection measure," clarifies Grambke. "We collaborate with well-known manufacturers which provide us with these solutions." The cables arrive in ISO standard lengths of 2,000 metres, which are wound on 2.5-metre-wide wooden drums, each weighing multiple tonnes. "We cut the cables individually according to the customer's needs," says Dirk Grambke. "Very few companies in Germany still offer this kind of service."

For one customer, that could mean 150 metres, but 500 metres for another, which is why pei tel precuts their cables into standardized lengths. This off-the-shelf availability saves an enormous amount of time. Custom-cutting cables to length is also important, as it makes transporting the cable drums to and on the worksite that much easier, because, typically, the drums are transported using small vans. pei tel cuts the requested length of cable from the massive stock drum, then winds the new section of cable onto smaller drums. For this, the specialists from the HELUKABEL subsidiary KABELMAT Wickeltechnik have installed an automatic winding line. The cable manufacturer themself recommended this supplier who delivered with an UMROL 2000 unwinder and an UMROL 1800 winder.

"The systems are not off the rack," explains KABELMAT sales consultant Manfred Wössner. This is because high-frequency cables are very delicate. Any alteration at all to the cables could impact its electrical characteristics and lead to malfunctions. The worst-case scenario is that the cables are no longer usable after being wound. "To prevent the cables from being deformed by the machine, we installed a belt length measuring device," says Wössner. "This device spreads the contact pressure across multiple rollers and thereby protects the cable." It is also important to keep in mind that the cables should not be subjected to high tensile forces, since these can not only change the length of the cable, but also its shape. "The machines run perfectly in-sync and are controlled using traction force," describes Wössner. "The winder and unwinder are perfectly coordinated. This relies heavily on the settings of the installed servo motors." KABELMAT also adjusted the machines to prevent the cables from being bent too excessively and becoming damaged.

Only one person is needed to control the line. The operator is able to adjust the tensile strength and speed between the two winders using a state-of-the-art Siemens touch panel and is able to follow the process in real-time on a monitor. The UMROL 1800 is designed to be able to wind cables, depending on their type, onto drums or rings, however, radiating cables are typically wound onto the classic wooden drums. After cutting the cable, a second operator removes the filled drum from the system and packs it onto a pallet. These are then transported for dispatch by a forklift. Meanwhile, the operator is able to take care of the next drum.

For pei tel, safety plays an important role. Safety grates, for instance, prevent employees from reaching inside the machines, and motion sensors stop the machines if a body part is detected inside of a dangerous area. "All KABELMAT machines are calibrated in accordance with the European Measuring Instruments Directive (MID) and are thus approved for use throughout Europe," explains Wössner. All steps of the operation are saved to a data storage device and can be seamlessly tracked. "All of this is to ensure we're offering our customers the highest quality and maximum uptime."

"After everything was up and running, KABELMAT provided the operating personnel from pei tel with intensive training and answered all of their questions," adds Dirk Grambke. He is, after all, enthusiastic about after-sales service. "If a problem arises, KABELMAT technicians can connect to our system remotely from their location in the Black Forest, initiate a remote diagnosis, and, if necessary, change certain parameters." This minimizes downtime and contributes to the efficiency of the operation, because every minute of downtime costs money.

Thanks to the new KABELMAT winding line, pei tel is able to quickly and affordably deliver custom-cut lengths of sensitive radiating cable without the fear of damaging them.